Cryptology ePrint Archive: Report 2005/131

Dynamic Group Key Agreement in Tree-Based Setting

Ratna Dutta and Rana Barua

Abstract: We present a provably secure tree based authenticated group key agreement protocol in dynamic scenario. Bilinear pairing and multi-signature are at the heart of our protocol. We prove that our protocol is provably secure in the standard security model of Bresson et al. An appropriate modification of Katz-Yung approach to tree based setting is adopted while proving its security against active adversaries. The protocol has an in-built hierarchical structure that makes it desirable for certain applications.